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Node.js assert.ok() Method

❮ Assert Module


Example

If an expression evaluates to 0 or false, an error is thrown and the program is terminated:

var assert = require('assert');
assert.ok(50 > 70);
Run example »

Definition and Usage

The assert.ok() method tests if a given expression is true or not.

If the expression evaluates to 0, or false, an assertion failure is being caused, and the program is terminated.


Syntax

 assert.ok(expression, message);

Parameter Values

Parameter Description
expression Required. Specifies an expression to be evaluated
message Optional. Specifies the error message to be assigned to the AssertionError. If omitted, a default message is assigned

Technical Details

Return Value: None
Node.js Version: 0.1.21

More Examples

Example

Using the message parameter:

var assert = require('assert');
assert.ok(50 > 70, "My message goes here");
Run example »

Example

The assert.ok() method also throws an error if the expression evaluates to 0:

var assert = require('assert');
assert.ok(50 - 50);
Run example »

❮ Assert Module

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